Malin Ah-King

621
Charles E. Young Dr. S

Department
of Ecology & Evolutionary Biology

University
of California, Los Angeles

Los
Angeles, CA 90095

Phone:
(424) 249 2746

E-mail:
mahking@ucla.edu

I'm a post-doctoral researcher at department of Ecology and
Evolutionary Biology, UCLA. I'm currently collaborating with
Patricia Gowaty on two projects, a phylogenetic study of the
evolution of sex chromosomes and a review of flexible mate
choice. I have a PhD from the department of Zoology Stockholm
University, Sweden and have also been a post-doc at the Centre
for Gender Research at Uppsala University, Sweden.

Research:

The
diversity in sex determination mechanisms in animals is
enormous, shifting frequently between genetic and environmental
sex determination and female and male heterogametic systems.
Several explanations have been proposed to account for the
evolution of sex determining mechanisms, however, most of these
explanations are proximate. Here we suggest a novel ultimate
hypothesis - that parental conflict over sex ratio is an
important selective force favouring the evolution of
heterogamety. The heterogametic sex can be seen as a momentary
winner of the conflict. Once heterogamety has evolved, the idea
predicts that the homogametic sex will evolve counter strategies
to win back or increase its control over offspring sex ratio,
such as parental care or internal fertilization.

One
important assumption of this hypothesis is that there are
ecological situations that promote the conflict between the
parents. If parents have no interaction with their offspring
after spawning, e.g. in pelagic spawners, there would be no
selection for sex chromosomes.

We
will conduct a phylogenetic study of evolution of heterogametic
sex determination in fishes in relation to habitat, parental
care and internal versus external fertilization. Fish are ideal
for testing this hypothesis since both parental care and sex
chromosomes has evolved numerous times in this taxon.

This
project is important because it addresses the adaptive
significance of sex chromosomes from the perspective of one of
the most well respected and influential ideas about natural
selection, namely Fisher's theory of the evolution of progeny
sex ratios.

Flexible mate choice

The
literature of mate choice is now vast, in this project we review
recent empirical evidence of flexible mate choice in diverse
taxa showing that individuals commonly change their behavior
depending on the social or ecological situations they are
experiencing. Likewise, recent theory says that accepting or
rejecting potential mates (being "choosy" or
"indiscriminate") changes as a function of, for
example, encounters with potential mates, the focal individual's
survival probability, and the size of the pool of potential
mates. Observations demonstrate that adaptive flexibility in
reproductive decision-making is apparently ubiquitous occurring
in both males and females of most species. We therefore
emphasize currently unanswered empirical questions about the
distribution of flexibility in reproductive decisions of
individuals.

Other
collaboration projects

In order to
depart from thinking about biological sex as something static,
we would like to develop the concept that in an evolutionary
perspective sex can be viewed as a reaction norm. Sex
determination itself is plastic. In humans, genes on the sex
chromosomes decide the inner environment that makes secondary
sexual characteristics develop, but they develop from genes that
actually exist in both sexes. In many other species, sex
determination is even more plastic with for instance ambient
temperature determining to which sex an individual will develop,
and changes in sex later in life also occur in a range of
species. Viewing sex as the result of an interplay between
genes and the environment - a reaction norm - could facilitate a
gender-neutral understanding of sex and sex differences in
behaviour. From this point of view, sexual differences are not
expected to generally fall into neat, discrete, pre-determined
classes.

We review
definitions of sex roles in animals and how they have been used
for different animal groups. Is there a problem with putting
this range of behaviours into the dichotomy of species with
sex-role reversal and those with conventional sex roles? What
about the antropomorphism? Could we depart from using the term
sex roles in biology?

Call for papers
(deadline May 1, 2010):

Challenging
Popular Myths of Sex, Gender and Biology

This
call for papers is for a transdisciplinary anthology about
gender and biology written by international researchers, aimed
at a public audience. Empirical research in biology, psychology,
and other life sciences sometimes undergirds popular notions of
female and male sexual difference, while much of current biology
actually opens a space for variable and non-static views of sex
and gender; instead of emphasizing dichotomous difference, the
natural sciences may look into sameness and the continuum of
morphologies, behaviors and processes in between. Our aim is to
make these insights public knowledge.